[PropelBridge] PropelTypeGuesser can now recognize columns by their phpName

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Until now, the `PropelTypeGuesser` could only find columns by their name.
Example: `created_at` was recognized but `createdAt` wasn't.

This PR adds the ability to match column's phpNames (in a case-insensitive way).